The following test will fail:

    @Test(dataProvider = "zipfsMap")
    public void zipSizeTest(final Map<String, String> env,
                            final int compression) throws Exception {
        Path osFile = Path.of("GrandSlams.txt");
        Files.deleteIfExists(osFile);
        Files.writeString(osFile, THE_SLAMS);
        Entry e0 = Entry.of("Entry-0", compression, THE_SLAMS);
        Path zipFile = generatePath(HERE, "test", ".zip");
        Files.deleteIfExists(zipFile);
        zip(zipFile,env, e0);

        try (FileSystem zipfs = FileSystems.newFileSystem(zipFile, env);
             SeekableByteChannel sch = Files.newByteChannel(zipfs.getPath(e0.name), Set.of(READ, WRITE))) {
            System.out.printf("File size=%s, channel size=%s %n", THE_SLAMS.length(), sch.size());
            assertEquals(sch.size(), THE_SLAMS.length());
        }
        try (FileSystem zipfs = FileSystems.newFileSystem(zipFile, env);
             SeekableByteChannel sch = Files.newByteChannel(zipfs.getPath(e0.name), Set.of(WRITE))) {
            System.out.printf("File size=%s, channel size=%s %n", THE_SLAMS.length(), sch.size());
            assertEquals(sch.size(), THE_SLAMS.length());
        }
        try (FileSystem zipfs = FileSystems.newFileSystem(zipFile, env);
             SeekableByteChannel sch = Files.newByteChannel(zipfs.getPath(e0.name), Set.of(APPEND))) {
            System.out.printf("File size=%s, channel size=%s %n", THE_SLAMS.length(), sch.size());
            assertEquals(sch.size(), THE_SLAMS.length());
        }
        Files.deleteIfExists(zipFile);
    }

The error is:

------------------
java.lang.AssertionError: expected [69] but found [0]
Expected :69
Actual :0
<Click to see difference>


at org.testng.Assert.fail(Assert.java:96)
at org.testng.Assert.failNotEquals(Assert.java:776)
at org.testng.Assert.assertEqualsImpl(Assert.java:137)
at org.testng.Assert.assertEquals(Assert.java:118)
at org.testng.Assert.assertEquals(Assert.java:547)
at org.testng.Assert.assertEquals(Assert.java:557)
at test.FailingChannelTests.zipSizeTest(FailingChannelTests.java:135)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:564)
at org.testng.internal.MethodInvocationHelper.invokeMethod(MethodInvocationHelper.java:124)
at org.testng.internal.Invoker.invokeMethod(Invoker.java:583)
at org.testng.internal.Invoker.invokeTestMethod(Invoker.java:719)
at org.testng.internal.Invoker.invokeTestMethods(Invoker.java:989)
at org.testng.internal.TestMethodWorker.invokeTestMethods(TestMethodWorker.java:125)
at org.testng.internal.TestMethodWorker.run(TestMethodWorker.java:109)
at org.testng.TestRunner.privateRun(TestRunner.java:648)
at org.testng.TestRunner.run(TestRunner.java:505)
at org.testng.SuiteRunner.runTest(SuiteRunner.java:455)
at org.testng.SuiteRunner.runSequentially(SuiteRunner.java:450)
at org.testng.SuiteRunner.privateRun(SuiteRunner.java:415)
at org.testng.SuiteRunner.run(SuiteRunner.java:364)
at org.testng.SuiteRunnerWorker.runSuite(SuiteRunnerWorker.java:52)
at org.testng.SuiteRunnerWorker.run(SuiteRunnerWorker.java:84)
at org.testng.TestNG.runSuitesSequentially(TestNG.java:1208)
at org.testng.TestNG.runSuitesLocally(TestNG.java:1137)
at org.testng.TestNG.runSuites(TestNG.java:1049)
at org.testng.TestNG.run(TestNG.java:1017)
at com.intellij.rt.testng.IDEARemoteTestNG.run(IDEARemoteTestNG.java:66)
at com.intellij.rt.testng.RemoteTestNGStarter.main(RemoteTestNGStarter.java:110)

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